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Re: Parallel and Series LCR Circuit Qs



Hi Bill,

At 09:24 PM 8/10/00 -0600, you wrote:
>On that fateful day 8/10/00 6:34 PM, thus spake Tesla list:
>
>> It really is three ohms which is pretty close.  If the primary current is
>> 12 amps RMS ( a typical primary RMS current), that resistor will burn off a
>> whooping 432 watts.
>
>Ah, but it's that first bang we're interested in, isn't it?  And doncha
>think the peak current in that first pulse is a wee bit higher than 12 amps?
>
snip...

The peak current is about 600 amps!!  However, that is only a brief 1% duty
cycle pulse.  If you look at the continuous equivalent current (the RMS
value) it is far lower, about 12 amps on my coil.  The RMS value of primary
current is extremely useful for determining capacitor ratings and such.
One has to be a little carful about using the AC resistances with skin
effects in the calculations, but the RMS primary current value really can
tell you many things.  In this case, it tells the power lost to the gap and
that I need about four 3amp RMS cap strings for the primary cap...

RMS primary current equations are giving in the notes at:

http://users.better-dot-org/tfritz/site/MMCinfo/MMCPower4.html


Cheers,

	Terry